Washington -LRB- CNN -RRB- -- Michelle Obama has n't given any indication that she 'll run for political office , but Sen. Mark Kirk is suggesting otherwise .

The Illinois Republican sent a fund-raising letter to supporters referring to the `` press and rumor mills '' that Obama may run for Kirk 's Senate seat in 2016 . The letter was first reported by the Chicago-Sun Times and confirmed by Kirk 's office .

Kirk even compares Obama 's potential run to speculation in 1999 over whether then-First Lady Hillary Clinton would run for the Senate . She eventually did .

So is Kirk looking for supporters to connect the dots ?

Kirk also writes in the letter that he is `` not one to believe rumors or engage in political gossip , '' but he takes `` all potential threats seriously . ''

`` Help me fend off a challenge from a Democratic opponent who will be backed by the national Democrat party as well as the home state political operation of the President , '' Kirk writes .

Capping off the letter , Kirk asks his supporters to open their wallets and drop $ 25 to $ 1,000 to help him stave off those types of `` threats . ''

The first lady 's office declined to comment on the fund-raising appeal .

While the `` rumor mill '' has been active for some time , Obama has explicitly said she has no plans for elected office .

Asked by ABC 's Robin Roberts whether her next move will be political , Obama said , `` No , it will not be political , '' and went on to say her next role will be `` mission-based '' and `` service-focused . ''

White House senior adviser Valerie Jarrett , a close friend of the Obamas , flat out rejected the suggestion that Obama would ever run for political office .

`` No . I 'm absolutely 100 percent positive that will never happen , '' Jarrett said on NBC 's `` Meet the Press '' in June .

That came less than a month after President Barack Obama himself said there was no chance .

`` One thing I can promise you is that Michelle will not run for office , '' Obama said in an interview with ABC in May .

First lady to campaign for Democrat in tight Iowa Senate race

Michelle Obama hits the campaign trail

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Sen. Kirk implies in a fund-raising email the first lady may run for his Senate seat

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Kirk ties the Obama `` rumor '' to 1999 suggestions Hillary Clinton would run for Senate

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He asks supporters to help him `` fend off a challenge from a Democratic opponent ''

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But even the President has said there 's no chance Michelle Obama will ever run for office